Answer:

It is checked whether there exists a data stream for each PID that occurs. This error might occur where TS are multiplexed, or demultiplexed and again remultiplexed.

The user specified period should not exceed 5 s for video or audio PIDs (see note). Data services and audio services with ISO 639 [17] language descriptor with type greater than '0' should be excluded from this 5 s limit.

NOTE: For PIDs carrying other information such as sub-titles, data services or audio services with ISO 639 [17] language descriptor with type greater than '0', the time between two consecutive packets of the same PID may be significantly longer.

In principle, a different user specified period could be defined for each PID.